In this section we will just take a couple of examples that show how easy it is to expose ourselves to long-term damage inadvertently. Pesticides, developed to control insects and other vermin, can increase agricultural productivity. Although pesticides were originally hailed as one of the wonders of modern technology, it was quite quickly discovered that there was a downside to their widespread use. One problem was that of bioaccumulation. Pesticides tended to be stable chemicals and

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Human activity has been responsible for some extinctions and othe deleterious changes to habitats. These changes have not always been the result of thoughtless or selfish behaviour; often intentions were worthy, but outcomes were not as predicted. The importance of genetic diversith is demonstrated here in relation to Dutch Elm disease. The need to retain genetic diversity in plants, used for food and medicine, is recognized in such initiatives as the Kew Milennium Seed Bank Appeal.

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What do we mean by energy and sustainability, and what is meant by future?

The term energy has a long history but the standard scientific definition today is that energy is the capacity to do work. The term power is related to energy and its definition is power is the rate of doing work. The two are linked together by the simple formula

energy = power x time

The term sustainability is not so simple to define but there is perhaps no better

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One of the greatest challenges facing humanity during the twenty-first century must surely be that of giving everyone on the planet access to safe, clean and sustainable energy supplies.

Throughout history, the use of energy has been central to the functioning and development of human societies. But during the nineteenth and twentieth centuries, humanity learned how to harness the highly-concentrated forms of energy contained within fossil fuels. These provided the power that drove the

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After a decade of controversy about the possible effects of CFCs, in 1985 British scientists discovered over the Antarctic a quite unexpected ‘hole’ in the ozone layer which was the size of the USA. This helped to galvanise the international community into action (though some who took part in the negotiations claim it played little part). By 1987 the first international agreement to control substances damaging to the ozone layer, the Montreal Protocol, was established. Interestingl

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The second source of criticisms that we would like to explore comes from feminist critiques. Some feminists argue that the universal notion of rights makes invisible the special problems faced by women as a group, and that, thereby, specific articles of the various human rights declarations and conventions reinforce traditional gender roles in the family and the workplace. This criticism comes in at least two forms.

The first is that rights for women (as for other disadvantaged groups)

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With regard to the first set of problems – that the rights discourse is not universal but is deeply informed by a Western perspective – it is striking that many actors and commentators on the international stage now frame their arguments and assertions in terms of the language of rights and justice. Yet we need to ask to what extent this language of rights and justice really underpins shared understandings and values. There is a strong case for saying that if there are shared understandin

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The modern discourse of universal human rights has a number of features. The idea that everyone, everywhere has rights refers to the concept that there are certain entitlements justifiably owed to all individuals by virtue of certain features that all human beings have in common. As the nineteenth-century French politician and historian Alexis de Tocqueville put it, the idea of rights ‘removes from any request its supplicant character, and places the one who claims it on the same level as t

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Clearly, it is not possible to devise a set of rules which, if followed, would lead inexorably to team effectiveness. The determinants of a successful team are complex and not equivalent to following a set of prescriptions. However, the results of poor teamworking can be expensive, so it is useful to draw on research, experience and case studies to explore some general guidelines. What do I mean by ‘team effectiveness'? – the achievement of goals alone? Where do the achievements of indivi

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Different team structures have different advantages and disadvantages. A structure may fit a particular task in one organisation better than another. On the next page, Table 1 sets out the strengths and weaknesses of different team structures.

Table 1 Strengths and weaknesses of different structures for project teams

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Among the common thermoplastics available in the mid-1970s, polypropylene appeared as a front runner on grounds of toughness, density and cost Table 9). However, it is subject to creep (being uncrosslinked) and possesses a low tensile modulus of ca. 1500 MN m−2. Its merit index is 12.7 due to the low density of 0.

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Replacement of one polymeric material by another may be undertaken entirely for manufacturing reasons, and this is what happened in the redesign of the Topper dinghy for thermoplastic polymer. The dinghy was originally designed for hand lay-up GRP in 1969 by Ian Proctor, a well known designer of small boats and yachts (Figure 61

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Good design fulfils the product specification under the required service conditions as well as contributing to the cost effectiveness of its manufacture and maintenance. The product specification itself must be an interpretation of the market needs. Hence good design means giving product appeal at the point of sale. Selecting the polymer is just one stage in this design exercise, both in terms of information on various properties of materials, as well as the detailed evaluation and selection

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While the identified objectives and constraints have been referred to constantly during the development stage, the testing stage of the approach is a more formal analysis of each option. Its objective is to determine whether:

the option will meet the operational objectives

it is technically feasible

it is organisationally feasible

it will meet the financial objectives.

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1000BASE-SX, for transmission over multimode fibre using an LED in the 800 nm window (the wavelength is specified to be between 770 and 860 nm). The specification is for up to 275 m on 62.5/125 mm multimode fibre, or 550 m on 50/125 mm multimode fibre;

1000BASE-LX, for transmission over multimode or single-mode fibre using a laser in the 1300 nm window (specified to be between 1270 and 1355

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